Don't go too crazy with study as you will burn yourself out by 6th year and will have no motivation to study then. After written homework you should spend maybe 2 hours-2 and a half hours studying and just study what you've done that day. Learn it well so when you need to learn it for an exam it will only be revision!

Honestly, 1-2 hours is enough for 5th year. Perhaps you can add more around the time your Halloween/Mid-term/Christmas/Summer exams are ahead, but I believe you do not need any more than that.

Though, studying has no limits whatsoever, if you want to study for hours and hours - go right ahead! Maintaining great grades and knowing everything in 5th year will be a MASSIVE help to you in the future around the time of your Leaving Certificate and you will find things so much easier.

And as a tip, do not just write and write and write stuff without understanding your material. Sure it does help, but the Leaving Certificate requires understanding of your subjects and their sections and all their terms. Sometimes instead of spending time writing away a ton of stuff you will barely remember in a week, spend some time pretending to be Plato or Aristotle, get your stuff out and just contemplate about your subject materials, e.g. Why must this formula be used for this type of question? What purpose is alcohol in this experiment? What was the poet experiencing & feeling while writing this poem? Why is this particular grammar rule always applied to these types of words?